Acne is a multifactorial disease with alterations in sebum composition and output and androgen metabolism recognized as agents in its etiopathogenesis. We have conducted for the past two years a longitudinal prospective study of sebum composition as influenced by changes in androgen status in 60 children ages 7 through 11. We have identified changes in the character of sebum at puberty which may be critical in producing acne. We wish to continue to follow longitudinally changes in sebum composition as correlated with pubertal staging, urinary androgen output and the appearance of comedos, papules, pustules, and graded acnes in our study population. The UCLA Health Sciences Computing Facility is providing personnel and facilities for the multivariate analysis of the data obtained.